Recently, with the problems of petroleum-based industries such as global warming and serious fluctuations and increase in the cost of petroleum and the like, bio-based chemical and energy industries have received attention. Bio-diesel, a bio-fuel, is produced by the ester change reaction of triglyceride from vegetable oil or animal fat. Due to the mass-production of bio-diesel, the production of glycerol by-products rapidly increased, and the cost of the mass-produced glycerol is continuously decreasing. It is expected that in the future, with increased market demand for bio-diesel, the production amount of the glycerol by-products will rapidly increase and the cost of glycerol will be further lowered.
Glycerol may be used as fats and fatty oils, fiber, antistatic agents of leather, and raw material of emulsifiers for cleaning. In addition, it may also be used as a carbon source for microorganisms, and thus, various chemicals may be produced based on microorganisms using the same. Among them, 3-hydroxypropionic acid (3-HP) is a promising platform chemical raw material that can be used as a raw material of various chemicals, along with lactic acid and succinic acid, and it may be produced from microorganisms based on glycerol. 3-HP has two functional groups that perform important functions for the synthesis of optically active materials, which is an element causing 3-HP to be highly favored as an important precursor in the chemical industry. The main compounds synthesized using 3-HP as a precursor include acrylic acid (MW 72.06), malonic acid (MW 104.06), 1,3-propanediol (MW 76.06) and the like (See FIG. 1).
As shown in FIG. 1, biologically, 3-HP may be produced from glycerol through dehydration and oxidation processes catalyzed by two kinds of enzymes. Using the first enzyme, glycerol dehydratase, glycerol is dehydrated and converted into 3-hydroxypropionaldehyde (3-HPA), and the second enzyme 3-hydroxypropionaldehyde dehydrogenase (3-HPA dehydrogenase) oxidizes 3-HPA to produce 3-HP.
Glycerol dehydratase is classified into two kinds according to the method of action.
First, Clostridium butyricum-derived glycerol dehydratase is a vitamin B12 non-dependent enzyme, and was reported to show the activity without aid of vitamin B12, but it has extreme oxygen sensitivity (PNAS, 100: pp 5010-5015 (2003)). Although the production of 3-HP using the vitamin B12 non-dependent glycerol dehydratase does not require vitamin B12 and thus may lower the unit cost of production, when a recombinant microorganism is made to produce 3-HP, it has a difficulty with fermentation due to extremely high oxygen sensitivity.
Next, Klebsiella pneumonia-derived glycerol dehydratase is known as a vitamin B12-dependent enzyme (U.S. Pat. No. 6,852,517). It is a vitamin B12-dependent enzyme, and although vitamin B12 should be added when used for the production of 3-HP, it exhibits high activity in common aerobic microorganism including E. coli, and thus, is relatively favorable for the production of 3-HP with high concentration compared to the vitamin non-dependent enzyme.
Meanwhile, 3-HPA, which is an intermediate in the production of 3-HP, may also be used as an intermediate for producing 1,3-propanediol (PDO). Namely, after glycerol is converted into 3-HPA, it may be converted into 1,3-propanediol by 1,3-PDO oxidoreductase, and in order to increase the production of 3-HP, it is required to inhibit the production of 1,3-PDO.